Plaster mixer



April 16, 1929. G. JAEGER 1,708,947

PLASTER MIXER Filed Nov. 15, 1927 2 Sheets-Sheet l Buncntor G'EBHARD JAEGER All/Q (Ittorneg S April 16, 1929. G. JAEGER 1,708,947

PLASTER MIXER Filed Nov. 15, 1927 2 Sheets-Sheet 2 3nnentor GEBHARD JAEGER Gttorncgj Patented Apr. 16 1929.

UNITED STATES GEBHARD JAEGER, OF COLUMBUS, OHIO.

PLASTER MIXER.

Application filed November 15, 1927. Serial No. 233,494.

This invention relates more particularly to plaster mixing machines of the variety in which blades are rotated in a cylindrical drum containing the plaster ingredients. The principal object of the invention is the provision of an improved form of blade two or more of them being so placed as to break up central masses of the aggregate and throw them back and forth longitudinally within the drum and thereby effect a more rapid and thorough mixing of the materials. Another object of the invention is to so form and place such blades that they act to clear the sides of the drum of the plaster being mixed and thereby aid in effecting the mixing of all of the material and prevent caking of the wall with unmixed or insufficiently mixed materials. Other objects and advantages of the invention will appear from the disclosure herein.

The invention is embodied in the example herein shown and described the features of novelty being finally claimed.

1n the accompanying drawings Figure 1 is a view in side elevation of a machine according to the invention.

1E ig. 2 is a view with the head of the engine side of the drum removed exposing the mixing devices therein in end view.

Fig. 3 is an elevation looking at the left hand end of the machine as seen in Fig. 1.

lFig. 4 is a top plan view of the drum.

Fig. 5 is a view of the shaft and mixing blades removed from the machine and looking at the faces of the blades.

Fig. 6 is a similar view looking mainly atthe edges of the blades.

In the views 10 designates a drum that is open at its upper side and is mounted to rock in suitable hearings on standards 11 rising from a truck bed 12.

Journaled in suitable hearings in the opposite ends of the drum 10 is :1V shaft 13 to the ends of which Within the drum are secured end arms 14, 14, extending from the shaft in opposite directions; and middle arms 15, 15, the latter also extending from the shaft in 01)- posite directions but each in a plane, at an acute angle to its companion end arm 14. To

the outer end of each arm 14 and its companion arm 15 is connected ablade of peculiar form, said blade having a longer portion 16 that is axially twisted in one direction and a shorter portion 17 standing inward toward the shaft at an angle to the longer portion, said shorter portion being slightly axially twisted in a direction the reverse of the portion 16 (see Fig. 6). One each of these blades is shown as connected to the outer end of one of the arms 14 and to its companion middle arm 15; and when so connected the longer portion 16 of the blade lies in'a path inclined to its motion, and its outer edge travels in close proximity to the interior surface of the drum for substantially half its length thereby 1n operation tending continuall to clear said surface of plaster and impel t e plaster generally toward the axis and middle of the drum. The shorter portion 17 of each blade inclines inward toward the middle of the drum and is so positioned, that it tends to move the plaster from the middle toward the end of the drum. In practice the shaft 13 is turned to move the blade in the direction indicated by the arrow in Fig. 2. It will therefore be 0 served that the Joint action of the two portions of the respective blades is such as to cause a stirring of the plaster in a back and forth manner longitudinally of the drum and from the two ends of the drum and from points near but beyond the middle of the drum toward the opposite ends across the middle of the drum.

The shanks of the end arms 14, 14, are shown as equipped with wideblades 18, each having an inclination like that of the main part 16 of the longitudinally extended blade, the end edge of the blade 18 traveling close to the head of the drum and said blade tending progressively to impel the plaster away from the head and toward the middle of the drum where it is reoperated on by the inwardly extending portion 17 of the main blade. The opposmg pressures of the blade in the different parts of the drum therefore cause a thorough stirring and mixing of the constituents of the plaster.

The drum is provided with a handle 19 for rocking it when it is to be discharged, a spent at 20 near one of the edges of the opening of the drum being provided for that purpose. The drum is also provided with means to hold it stationary while the mixing devices are being driven, said holding meansincluding a latch lever 21, pivoted on the truck bed 12 and having a shoulder at 21 to engage a stop 22 fixed on the rim of the drum near its end (see Fig. 1).

The shaft 13 containing the mixing blade is driven by a suitable engine (not shown) in a housing 23 operating ordinary gearing (not shown) in a case 24. Suitable levers such as shownl at 25 and 26 one at each end of the machine, said levers being connected by rod 27, are provided to operate a clutch mechanism in houisng 28 for connecting and disconnecting the power for driving shaft 13, such means being of ordinary constructlon and not shown.

The drum above the opening is provided with a suitable guard or grating 27 to protect workmen from injury by the mixing devices when rotating in the drum. The materials to be mixed are supplied to the drum through said grating 27.

Additional mixing blades (not shown) extending laterally from middle arm 15, 15, can, if desired, be bolted to said arms at the slots shown therein (see Fig. 5).

The forms of the parts can be changed without departin from the gist of the mvention as claime What I claim is 1'- 1. A mixing device of the class described, including a drum, a mixing means therein comprising a shaft having end and middle arms projecting therefrom, two blades attached to the ends of said arms, each consisting of a flat strip twisted axially in its main portion and lying generally in a direction nclined to its path of motion, said strip 1ncluding at its end an inwardly directed portion twisted in reverse of the twist in the main portion.

2. A mixing device of the class described, including a drum, a mixing means therein comprising a shaft having end and middle arms projecting therefrom, two blades attached to the ends of said arms, each consisting of a flat strip to travel in proximity of the inner peripheral surface of the drum and twisted axially in its main portion, and lying generally in a direction inclined to its path of motion, said strips each including at its end near the middle of the drum an inwardly directed portion twisted in reverse of the twist in the main portion.

3. A mixing device of the class described, including a drum, a mixing means therein, comprising a shaft having end and middle arms projecting therefrom, two blades attached to the ends of said arms, each consisting of a flat strip twisted axially in its main portion and lying generally in a direction inclined to its path of motion, said strips each having at its end near the middle of the drum an inwardly directed ortion twisted in reverse of the twist of t e main portion, and shorter blades attached to said end arm between the shaft and the main portion of the blade.

4. A mixing device of the class described, including a drum, a rotary mixing means therein comprising a shaft, end arms projecting therefrom, a blade attached at one end to the end of each of said arms, said blade including a main portion twisted axially and extending approximately half the length of the drum, and provided at its other end beyond the middle of the drum with a portion extending toward the axis of the drum twisted reversely to the twist of the main portion.

5. A mixing device of the class described, including a drum, a rotary mixing means therein comprising a shaft, end arms projecting therefrom, a blade attached at one end to each of said end arms, said blades each including a main portion twisted axially and extending approximately half the length of the drum, and inclined to the path of its motion, and provided at its other end with a portion extending toward the axis of the drum said portion twisted reversely to the twist of the main portion.

6. A mixing device of the class described, including a drum, a mixing means therein comprising a shaft having end and middle arms projecting therefrom, two blades attached to the ends of said arm, each consisting of a fiat strip lying in a direction inclined to the path of motion to force the mixed material toward the middle of the drum, said strip including at its end an inwardly directed part inclined to its path of motion and tending to force the mixed material toward the ends of the drum.

, GEBHARD JAEGER. 

